摘要
针对现行高地应力判据在软质围岩大变形及岩体强度在15~60 MPa区段适用性不足的问题,通过现场测试、案例调研、理论分析与有限元模拟相结合的方法,探讨适用于全岩体强度范围的高地应力判识准则。主要结论有:1)高地应力隧道灾变模式与岩体力学特性密切相关,岩体强度在15~60 MPa区段主要表现为松弛破碎与变形侵限;2)基于能量原理,提出岩体破碎过程中能量转化的非线性特征,即破碎耗散能随岩体强度及脆-韧性呈先升后降趋势,并据此提出最优岩体强度与最优脆性指数假设;3)基于岩体强度应力比,建立全岩体强度范围的高地应力判据,划分不同岩体强度范围的高地应力灾变类别,为不同地质条件下隧道工程灾害防控提供理论依据。
In response to the limited applicability of the currently accepted high-geostress criterion in soft surrounding rocks prone to large deformations and within a rock mass strength range of 15-60 MPa,the authors integrate in-situ testing,case history investigations,theoretical analyses,and finite-element modeling to develop an improved criterion applicable across the entire rock mass strength spectrum.The main conclusions are as follows:(1)The failure pattern of high-geostress tunnels is strongly controlled by the mechanical properties of the associated rock mass;within the 15-60 MPa strength range,relaxation-induced fracturing and excessive convergence predominate.(2)Based on energy principles,nonlinear energy conversion accompanying rock mass fracturing is revealed:energy dissipation during fragmentation initially increases and subsequently decreases with increasing rock mass strength and brittle-ductile transition index.This finding suggests an optimal rock mass strength and brittleness index.(3)A novel high-geostress criterion is proposed that is valid for all rock mass strengths,thereby providing a theoretical basis for hazard prevention and control in tunnel engineering under diverse geological conditions.These findings effectively overcome the limitations of existing criteria and provide clear engineering guidance.
作者
郭利民
李国良
祁占锋
李方芳
张景
GUO Limin;LI Guoliang;QI Zhanfeng;LI Fangfang;ZHANG Jing(State Key Laboratory of Intelligent Geotechnics and Tunnelling,Xi′an 710043,Shaanxi,China;China Railway First Survey and Design Institute Group Co.,Ltd.,Xi′an 710043,Shaanxi,China)
出处
《隧道建设(中英文)》
北大核心
2025年第10期1919-1925,共7页
Tunnel Construction
基金
中国铁建科研计划项目(2024-W24)。
关键词
隧道
高地应力判识
围岩大变形
松弛破碎
最优脆性指数
强度应力比
tunnel
high-geostress identification
large deformation of surrounding rock
loose and broken rocks
optimal brittleness index
strength-stress ratio
作者简介
第一作者:郭利民(1993-),男,甘肃会宁人,2017年毕业于清华大学,水利水电工程专业,硕士,高级工程师,现从事山岭隧道设计及科研工作。E-mail:guolimin13@foxmail.com。
